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Preparation of Fe_(3)O_(4)@C@TiO_(2)and its application for oxytetracycline hydrochloride adsorption

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Rare Metals 2020年第11期39卷 1333-1340页

作者： qi-Li hu Lin-Shan Wang Nan-Nan Yu Ze-Fei Zhang Xin Zheng Xiao-Min hu College of Science Northeastern UniversityShenyang 110819China College of Resources and Civil Engineering Northeastern UniversityShenyang 110819China

The magnetic Fe_(3)O_(4)@C@TiO_(2)microspheres with multilevel yolk-shell structure were successfully prepared by combining sol-gel and simple hydrothermal *** features of the as-obtained Fe_(3)O_(4)@C@TiO_(2)microspheres were investigated by Fourier transform infrared(FTIR)spectra,scanning electron microscopy(SEM),powder X-ray diffraction(XRD),N_(2)adsorptiondesorption measurements and transmission electron microscopy(TEM).Fe_(3)O_(4)@C@TiO_(2)was used as an adsorbent to explore its adsorption properties of oxytetracycline hydrochloride(OTC-HCl)by changing initial concentration and *** results suggest that the maximum adsorption of Fe_(3)O_(4)@C@TiO_(2)is 87.3 mg·g^(-1),and the time reaching the absorption equilibrium is 60 *** model fits to data better than the Freundlich model,and the kinetic properties are well described by the pseudo-second-order *** addition,the synthesized composites’reusability without obvious deterioration in performance is demonstrated by three cycles.

关键词： Fe_(3)O_(4)@C@TiO_(2) Adsorption Oxytetracycline hydrochloride Recycle

Automatic character detection and segmentation in natural scene images

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第1期8卷 63-71页

作者： Zhu Kai-hua qi Fei-hu JIANG Ren-jie XU Li Department of Computer Science and Technology Shanghai Jiao Tong University Shanghai 200030 China

We present a robust connected-component (CC) based method for automatic detection and segmentation of text in real-scene images. This technique can be applied in robot vision, sign recognition, meeting processing and video indexing. First, a Non-Linear Niblack method (NLNiblack) is proposed to decompose the image into candidate CCs. Then, all these CCs are fed into a cascade of classifiers trained by Adaboost algorithm. Each classifier in the cascade responds to one feature of the CC. Proposed here are 12 novel features which are insensitive to noise, scale, text orientation and text language. The classifier cascade allows non-text CCs of the image to be rapidly discarded while more computation is spent on promising text-like CCs. The CCs passing through the cascade are considered as text components and are used to form the segmentation result. A prototype system was built, with experimental results proving the effectiveness and efficiency of the proposed method.

关键词： Text detection and segmentation Adaboost NLNiblack decomposition method Attentional cascade

Research on discharge phenomenon caused by cross‐adsorption of linear insulating fibre and metal dust under DC voltage

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High Voltage 2022年第2期7卷 269-278页

作者： Ruixue Liang qi hu Heng Liu Jian Wang qingmin Li State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijingChina

A large amount of metal dust is often generated during production and operation of Gas Insulated Switchgear/Gas‐Insulated Transmission Line,and insulating fibres are very easy to mix in during *** discharge phenomenon induced by these two impurities remains *** setting up a test rig with parallel electrodes,the discharge characteristics of metal dust and linear insulating fibres under the negative DC voltage were studied separately and *** obtained research results indicate some interesting phenomena that the metal dust may render‘sand storm’motion characteristics under the action of the electric field,and the linear insulating fibres appear to show‘standing’,‘jumping’,‘flying fire’and other phenomena.A small amount of dust and fibres alone present little effect on the breakdown voltage of the air ***,while the insulating fibres and metal dust coexist,the metal dust will be adsorbed on the surface of the insulating fibres,then the surface charge of the fibres is reallocated,and the discharge phenomenon at both ends of the fibres is enhanced,so that the insulating fibre exhibits similar movement and discharge characteristics to the linear metal *** the same time,the fibres with dust absorbed on will result in an air gap breakdown voltage drop of approximately 25%-40%.What's more,if the discharge of fibres and the‘sand storm’movement of the dust coexist,it may directly lead to‘explosion’of the moving dust,causing severely ablation of the plate surfaces,and thereby the degree of destruction increases dramatically.

关键词： jointly fibre fibres

Sensitivity analysis of spacecraft in micrometeoroids and orbital debris environment based on panel method

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Defence Technology（防务技术） 2023年第1期19卷 126-142页

作者： Di-qi hu Run-qiang Chi Yu-yan Liu Bao-jun Pang Hypervelocity Impact Research Center Harbin Institute of Technology150080HarbinChina

To reduce the risk of mission failure caused by the MM/OD impact of the spacecraft,it is necessary to optimize the design of the *** survivability assessment is the key technology in the optimal design of *** survivability assessment includes spacecraft impact sensitivity analysis and spacecraft component vulnerability analysis under MM/OD *** impact sensitivity refers to the probability of a spacecraft encountering an MM/OD impact while in *** refers to the probability that each component of a spacecraft may fail or malfunction when impacted by space *** this paper mainly analyzes the impact sensitivity and proposes a spacecraft sensitivity assessment method under the MM/OD environment based on a panel *** this panel method,a spacecraft geometric model is discretized into small panels,and whether they are impacted by MM/OD or not is determined through the analysis of the shielding or shadowing relationships between *** number of impacts on each panel is obtained through calculation,and accordingly the probability of each spacecraft component encountering MM/OD impact can be acquired,thus generating the impact *** paper extracts data from the NASA’s ORDEM2000,the ESA’s MASTER8 as well as the SDEEM2015(Space Debris Environmental Engineering Model developed by HIT),and uses the PCHIP(Piecewise Cubic Hermite Interpolating Polynomial)method to interpolate and fit the size-flux relationship of space *** with linear interpolation and cubic spline interpolation,the fitting results through the method are relatively more *** feasibility of this method is also demonstrated through two actual examples shown in this paper,whose results are close to those from ESABASE,although there are some minor errors mainly due to different debris data *** the cross-check by three risk assessment software-BUMPER,MDPANTO and MODAOST-under standard operating condit

关键词： Shielding algorithm Panel method Spacecraft Sensitivity

Locking of Tearing Modes by the Error Field

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Chinese Physics Letters 2011年第9期28卷 190-193页

作者： XU Tao hu qi-Ming hu Xi-Wei YU qing-Quan J-TEXT Tokamak Laboratory State Key Laboratory of Advanced Electromagnetic Engineering and TechnologyCollege of Electric and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074 Max-Planck-Institute Für Plasmaphysik EURATOM Association85748 GarchingGermany

The locking of tearing modes by the error field is studied by nonlinear numerical *** threshold of mode locking for J-TEXT tokamak plasmas is found.

关键词： tokamak locking mode

Learning Causal Effect Using Machine Learning with Application to China's Typhoon

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Acta Mathematicae Applicatae Sinica 2020年第3期36卷 702-713页

作者： Peng WU qi-rui hu Xing-wei TONG Min WU School of Statistics Beijing Normal UniversityBeijing 100875China School of mathematics and Statistics Hubei University of Science and TechnologyHubei 437000China

Matching is a routinely used technique to balance covariates and thereby alleviate confounding bias in causal inference with observational *** of the matching literatures involve the estimating of propensity score with parametric model,which heavily depends on the model *** this paper,we employ machine learning and matching techniques to learn the average causal *** comparing a variety of machine learning methods in terms of propensity score under extensive scenarios,we find that the ensemble methods,especially generalized random forests,perform favorably with *** apply all the methods to the data of tropical storms that occurred on the mainland of China since 1949.

关键词： causal effect matching machine learning

Value of MR diffusion imaging in hepatic fibrosis and its correlations with serum indices

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World Journal of Gastroenterology 2014年第24期20卷 7964-7970页

作者： Xing-Rong hu Xian-Nian Cui qi-Tuo hu Jun Chen Department of Imaging The Central Hospital of Enshi Autonomous Prefecture The Enshi Clinical College of Wuhan University Department of Laboratory The Central Hospital of Enshi Autonomous Prefecture Medical school of hubei Institute for Nationalities Department of Radiology Renmin Hospital of Wuhan University

AIM: To compare apparent diffusion coefficient (ADC) values on diffusion-weighted imaging (DWI) of hepatic fibrosis patients with those of healthy controls and to identify their correlations with serum indices of live... 详细信息

关键词： Liver cirrhosis Diffusion-weighted imaging Hyaluronic acid Laminin Biological marker

Surface Charge Accumulation Characteristics on DC GIL Three-post Insulators Considering the Influence of Temperature Gradient

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CSEE Journal of Power and Energy Systems 2023年第5期9卷 1926-1934页

作者： qi hu qingmin Li Zhipeng Liu Naifan Xue Jian Wang Manu Haddad North China Electric Power University Beijing 102206China.He is now with State Grid Jiangxi Electric Power Co.Ltd.Nanchang 330077China the State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China the Advanced HV Engineering Research Centre Cardiff UniversityThe ParadeCardiff CF243AAU.K.

Surface charge accumulation is considered to be a critical factor in flashover failure of three-post ***,surface charge accumulation characteristics on threepost insulators with complex structures and uneven electric fields are still ***,the temperature gradient field makes charge accumulation more *** this presentation,surface charge profiles of DC three-post insulators under electro-thermal coupling stress are studied by establishing a multi-degree-of-freedom movement measurement *** abdominal area of the three-post insulator accumulaftes charges of identical polarity as the DC voltage,while the leg area accumulates heteropolar *** density from the bottom of the leg to the center of the abdomen presents a trimodal distribution pattern,including two homopolar charge peaks and one heteropolar charge *** surface conductance distribution arising from the temperature gradient leads to a significant increase in amplitude and distribution range of the homopolar charge peak at the legs of *** of the temperature gradient will further magnify the homopolar charge peak at the *** DC voltage is 100 kV and conductive pole temperature is 70℃,surface charge density of the three-post insulator can reach 100μC/m^(2).Therefore,surface conductance regulation of the leg region is the key to charge regulation and insulation optimization design of DC three-post insulators.

关键词： Charge accumulation charge measurement surface charge temperature gradient three-post insulator

激光定位引导下颅脑肿瘤穿刺活检术安全性和有效性的价值分析

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医师在线 2024年第9期14卷 42-44页

作者：古运涛翟聪胡奇杨刚岳阳市中心医院神经外科湖南岳阳414000

目的探究激光定位引导下颅脑肿瘤穿刺活检术安全性和有效性的价值。方法选取2023年1月~2023年12月我院收治的疑似颅脑肿瘤患者共96例,均进行激光定位引导下颅脑肿瘤穿刺活检术。分析所有患者的活检结果,评估穿刺活检的准确性和安全性。... 详细信息

目的探究激光定位引导下颅脑肿瘤穿刺活检术安全性和有效性的价值。方法选取2023年1月~2023年12月我院收治的疑似颅脑肿瘤患者共96例,均进行激光定位引导下颅脑肿瘤穿刺活检术。分析所有患者的活检结果,评估穿刺活检的准确性和安全性。结果激光定位引导下颅脑肿瘤穿刺活检术的病理结果显示,恶性肿瘤主要包括脑胶质瘤、弥漫性大B细胞瘤、肺癌脑转移、神经母细胞瘤,良性肿瘤包括炎性病变、胶质细胞增生;激光定位引导下颅脑肿瘤穿刺活检术阳性结果87例,阴性结果9例,其中假阴性3例,假阳性0例,准确度为96.88%(93/96),灵敏度为96.67%(87/90),特异度为100%(6/6);本研究96例患者中,出现并发症的患者共8例,3例患者出现局部小片出血,其中2例患者伴有轻微头痛的症状,经过3 d左右的观察,患者的症状均减轻;4例患者术后出现颅内高压,经过抗感染、雾化化痰、营养神经及降压治疗后,症状均好转;1例患者出现脑疝后死亡。结论激光定位引导下颅脑肿瘤穿刺活检术是一种有效的临床诊断方式,具有准确性高、安全性高的特点,对颅脑肿瘤的诊断有一定价值。

关键词：激光定位引导颅脑肿瘤穿刺活检安全性有效性